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effective

adj.
B1 Intermediate Oxford US //ˈifɛktɪv// UK //ɪfˈɛktɪv// ef·fec·tive General-service

adj. producing the result that you want. If a medicine or a plan works well, you say it is effective.

adj. successful in producing a desired or intended result. When used in a legal or official context, it describes a rule or law that is currently in operation.


SIMPLE

This new medicine is very effective against headaches.

CONTEXTUAL

The marketing team needs to find a more effective way to reach younger customers online.

COMPLEX

While the initial strategy appeared sound, it proved less effective in practice due to unforeseen logistical hurdles and a lack of clear communication between departments.

Synonyms
Antonyms
Origin

From French effectif, from Latin effectīvus (“productive; effective”), from efficiō (“I make; I bring about”), equivalent to effect + -ive.

Usage

Commonly followed by the preposition 'at' when describing a person's skills, or 'against' when describing a solution to a problem.

Pitfall

an efficient medicinean effective medicineLearners confuse 'effective' (producing the right result) with 'efficient' (working quickly without wasting time or effort).

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